Here is a simple scene in Bryce .br7 format with some domino pieces modelled using boolean operation.Feel free to play with the scene ,create more pieces using the set list as reference.You can resize the spheres,add new textures without ungrouping.Objects are grouped, you can convert it as mesh to create an obj and use as reference in Hexagon modelling too.

If you are new to boolean modeling i suggest you to take a look at my basics boolean tutorial pdf.